Whoever is having cycling problems with an SBE or SBE 2 is not cleaning their weapon properly. I have cleaned many SBEs for my hunters that were "single shots" and once I got done with them, they never malfunctioned again. The problem I see with them not cycling low brass shells is due to people oiling the crap out of them when they clean them. Run the gun dry or just a drop of oil, and it will not screw up.